A good comprehensive guide to alternative energy sources. However, the content was extremely repetitive. The entire book could have been condensed to half (or even less) of its current text. Many paragraphs repeat what was just said 1-2 paragraphs earlier. But other than this, the book was easy to read and understand (very little jargon), and provided a good list of pros and cons for each energy source discussed, backing each point with reason and evidence.